Finished the 50hr maintenance this evening. This guide was very helpful, thanks again! It would have taken me much longer without this guide.
Just a few additional notes I found that might help the next guy...
1. All of my drain plugs were extremely tight, especially the middle HST one.
2. The HST filter was on so tight it took me 45 minutes of messing around to get it off. I tried every filter wrench in my toolbox, the cup style and clamp (like giant channel-lock style) with no luck. I ended up going old school, jamming a screwdriver through the filter to get it loose. What a mess that was. Love the feeling of stinky, sticky HST fluid running down my forearm into my armpit. Good times. They must have put that filter on with an impact wrench at the factory. Insanely and unnecessarily tight.
3. I used brake cleaner to clean the suction screen, worked great.
4. I think how well you get the fluids to drain might be at least a little dependent on the angle of the tractor. I noticed I didn't use all of the HST fluid that I bought, almost one full jug left over with it filled to the line. I think it might have drained better/more if I had lowered the rear a bit more or tilted it to the side I was trying to drain.
5. After filling the HST fluid up to the dot I started the tractor and it immediately dropped, guessing to fill the filter. Turned it off, topped it off, then started again and ran the controls for the loader and 3 point as well as the forward and reverse moving only a foot or two. Turned it off, and checked the level again. Had to add a few more ounces.
6. Finally, I ran it a bit (15 minutes) using all the controls, parked it and checked all fluid levels again. Didn't need to add any more of anything.
7. Checked for leaks, thankfully none.
8. I had forgotten to clean the air filter the day before so I blew that out with an air hose. Really surprised at how much dirt/dust came out after only 48.x hours.
9. Warm shower to scrub the HST fluid out of places that stuff should never be, then a cold beer to celebrate.